However, findings from the few research studies on the ergogenic (. performance enhancing) effects of quercetin supplementation in humans are equivocal 122-127 . A small preliminary study showed that when given in combination with other antioxidants for 6 weeks, quercetin improved endurance time-trial performance on a bicycle ergometer in humans 126 . Another study, conducted by the same research team that showed performance enhancing effects in mice, gave healthy but untrained participants 500 mg of quercetin twice daily. After 7 days it was shown that the quercetin supplementation resulted in a modest increase in VO2max along with a substantial (%) increase in ride time to fatigue 125 . It was concluded that quercetin supplementation can increase endurance without previous exercise training in untrained participants 125 . In contrast, another controlled study conducted by another research team, which gave young healthy recreationally active men 1 g/day of quercetin in a sports hydration for 16 days failed to show any benefits over placebo; the quercetin supplementation did not improve neither muscle oxidative capacity or performance in a 10 min maximal-effort cycling test 124 . Also, supplementing with 1 g/day of quercetin for 3 weeks in trained cyclists failed to show a performance benefits 127 .